Rodents have plagued mankind for centuries by competing for food, spreading disease and by destroying the character of neighborhoods.
They have been known to attack humans, they foul foodstuffs with their droppings, dirt and parasites.
Over the year there have been many solutions proposed to eliminate rodent populations but, the most effective and widespread method of eliminating a rodent population has been to kill them with poisoned baits.
Baits have taken the form of impregnated grains and foods, formed into small pellets and poisons have been placed in various sizes of parafinized blocks.
Each of these forms have had inherent individual drawbacks such as the tendency of rodents to scatter impregnated grains and pellets and the reluctance or rodents, especially mice, to consume larger forms of bait blocks.
Additionally, the aforementioned methods of fabricating are defective for the following reasons; rodents, in spreading bait as they ate presented a significant potential for the poisoning of non target species and, even when bait was placed in tamper-resistant bait stations, there was a tendency for the bait to scatter as the rodents passed through the stations, or, if the stations were upset by activity in the environment.
When larger blocks of bait were fabricated out of material such as parafinized materials, the rodents, who have a tendency to nibble at their food sources would select more palitable alternative foods in the surrounding areas thereby defeating the control program.
House mice, who are particularly selective in their feeding habits, would ignore the larger bait blocks because they shyed away from baits offered in the forms that only provided flat surfaces that precluded their natural method of food consumption by knawing at the rough edges or small exposed surfaces of foods.
With the introduction of advanced and more powerful rodenticide products that were designed to destroy rodents in a single feeding, a method of presenting baits to target rodents such as Norway Rats, Roof Rats or House Mice in individual and metered portions that were more secure and stable became necessary.
In order to provide this, a method of providing a parafinized bait block that would afford a continous irregular surface for the rodent to knaw at and that would prvide a contious biting edge in order to make the bait more palatable, became an absolute necessity.
The object of the instant invention is to improve the state of the art in the presentation of baits to target rodents and to provide a structure of bait, in individually sized blocks, that will allow the rodent to consume the bait and, while consuming the bait, will cause the remaining portion of the bait block top have an irregular form and a biting edge that the rodents can knaw on.
Still another object of the instant invention is to provide a stable rodenticide that can be placed in a container or secured to a floor peg and, that will inhibit movement of the bait as it is consumed.
A further object of the invention is to provide a replicable and uniform individual bait block portion, constructed of parafinized material, that will be accepted by target rodents more readily.
Still another object of the invention is to conserve the amount of bait consumed by an individual rodent who, after injesting a rodenticide that requires multiple feedings, would normally remove and hide ramaining bait, even after consuming a lethal dose.
These, and other objects, advantages and novel features of the invention will become apparent from the following description of the invention when considered in conjunction with the accompanying drawings.
Reference is made to the following prior patents both U.S. and foreign 3105321 Link 10/63, Class 424, 1220593 Berg 3/17, Class 424, 1174695 Dawson 3/16, Class 424, 1156584 Bloom 10/15, Class 424, 2813058 Smith 11/57, Class 424, 3816610 Lusby 6/74, Class 424, 1915392 Rhomson 6/33, Class 426, 2132690 Hilliard 10/38, Class 424, 982711 Ellis 1/11 Class 426, 1695567 Weber 12/28, Class 426, D098858 Gager 3/36, Class D1, D89941 Low 5/33, Class 424, 3071496 Jacobs 12/63, Class 424, 376111 Tovey 3/83, Class 424--Foreign 717369 France, Mauler 10/31, Class 424, 0164102 Japan 12/81 Matswhita, Calss 424, 0013503 Japan, Kyowasangio 1/83, Calss 424, D068083 France, Renaud 1/83, Class 424 189400 Great Britain, Walton 11/22, Class 424352208 Italy Soc. A. Perigina 9/37, Class 424, 21156976 Great Britan, Walton 9/83, Calss 424, 2115698A, Great Britian Gschwind, Calss 424, 1233115 France, S.A.R.L. 10/60, Calss 424, 0120501 Japan Nitto Elec 9/80, Class 4240164101 Japan Matsushita 12/81, Calss 4240046901 Japan Matsuhita 3/81, Class 424.
The above cited patents are defective in that they are not readily replicable, depend on the addition of pisoned material to standard and available foodstuffs that do not maintain a regular and predicable pattern of continous knawing surfaces as they are consumed and do not take into account the effect of diverse toxins on differing species of household rodents, Additionally, the cited patents do not maintain a relationship between a predetermined patern of exterior protuberances and grooves and an internal structure of holes.
Further, the exterior pattern that appear on extruded or molded forms of food product as cited in the patents are designed to give the products extra strength in shipping and handling and are not claimed to provide a continous biting edge that appears as a rodent consumes the product or bait. Additionally, many of the cited patents contain flangible grooves used to break a larger portion of the product into smaller pieces. This is not in fact a feature of the present invention and the concept of flangible grooves to divide a larger unit to smaller pieces is not claimed in the instant invention.